In exchange for an undisclosed portion of the output from the massive Oyu Tolgoi Mine in Mongolia, commodity trader Trafigura will provide financing for the project.

Reuters reported that the announcement was made on Dec. 16 in Trafigura’s first fully-public annual report in its 20-year history.

Trafigura, which markets a wide range of metals including copper concentrate, referred to the off-take deal in its first fully public annual report since being set up 20 years ago.

"We also provide finance in exchange for long-term supplies. For instance, we recently signed an off-take agreement with Oyu Tolgoi in Mongolia," the report said.

Rio Tinto, majority owner and operator of Oyu Tolgoi, one of the world's largest copper and gold mines, has spent months wrangling with the Mongolian government about plans to expand from an openpit into an underground operation.

Rio Tinto put the mine’s $5 billion expansion on hold in July, saying the Mongolian government wanted parliament to approve the project’s financing. Mongolia hoped to resolve the dispute by early 2014, a government source told Reuters last month.

Fifteen banks that have agreed to finance the expansion have told Rio Tinto they will extend their commitments, which were due to expire at the end of the year, until next March, a statement said.

Trafigura also said the global copper market is expected to be broadly in balance next year as low inventories and a recovery in global growth offset stronger mine output.

“We don’t expect prices to rise markedly, but on the other hand, with concentrates trading at close to cost levels for some producing areas, a collapse in prices is also unlikely,” the Trafigura report said.

The benchmark copper price on the London Metal Exchange has shed 8.3 percent this year, weighed down by more output from new mines such as Oyu Tolgoi and improved operations at many existing mines.

The global copper market is expected to widen its surplus next year to 328,000 tons from 182,000 tons this year, analysts polled by Reuters said in October.